JPH10273839A - Crimped fiber excellent in fouling resistance, and carpet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain crimped fibers comprising fibers including a sheath and core type conjugated fiber consisting of a core part composed of a polyamide and a sheath part composed of a polyamide composition obtained by blending a fluorine-containing polymer with the polyamide, having specific crimp stretch ability and a number of crimp, excellent in fouling resistance and hardly fouled when used as a carpet. SOLUTION: This crimped fibers comprises fibers including sheath and core type conjugated fiber consisting of 40-90 wt.% core part composed of a polyamide and 10-60 wt.% sheath part composed of a polyamide composition obtained by blending a fluorine-containing polymer such as a random copolymer consisting essentially of tetrafluoroethylene and ethylene, polychlorotrifluoroethylene, polyvinylidene fluoride and a copolymer of vinylidene fluoride and tetrafluoroethylene, with the polyamide so that the fluorine content may be 0.05-5.0 wt.%. Further, the crimped fiber has crimp characteristics such as 10-40% crimp stretch ability, 6-12/in number of crimp. The fouling of a carpet is easily removed by laundry, when the crimped fiber is used as a carpet, and the crimped fibers are also useful for a string, a curtain, a fabric for a bag, a sheet, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crimped fiber and a carpet having excellent stain resistance. More specifically, the present invention relates to a stain-resistant crimped fiber and a carpet, which are extremely excellent in stain resistance as compared with conventional crimped fibers and carpets and can maintain the stain-resistant effect for a long period of time.

[0002]

2. Description of the Related Art In general, carpets have a drawback that when they are used for a long period of time, dirt easily penetrates into fibers and the dirt cannot be sufficiently removed even after washing.

[0003] In particular, polyamide carpets are disadvantageous in terms of stain resistance because the polyamide fibers themselves have the property that water can easily penetrate as compared with carpets using polyester or polypropylene.

However, polyamide carpets are overwhelmingly excellent in other carpet properties such as bulkiness, texture, durability, and dyeing property. Therefore, techniques for improving the stain resistance have been intensively studied. Have been. And, the stain resistance improvement technology has been applied mainly to carpets used in relatively high-grade zones.

[0005] As a conventional technique for improving the stain resistance of fiber for carpet, as described in, for example, US Pat. No. 1,292,388, the cross section of a single yarn of fiber for carpet is made square hollow. There is a method to make dirt less noticeable. This technology has been widely adopted practically because it has a considerably excellent effect of making the stain on the carpet difficult to see. However, it has no effect on preventing stains from adhering to the carpet fiber itself,
In particular, when used in applications that are easily soiled, the stain resistance was unsatisfactory.

As another method, there has been proposed a method of treating with a stain-proofing agent for improving stain resistance in a process of producing crimped fibers for carpet or a process after tufting of carpet. . In this method, an emulsion of a fluorine-containing compound is generally used as a treating agent,
This treating agent is applied to the surface of the fiber or carpet, and cured as required.

Specifically, for example, Japanese Patent Application Laid-Open No. 58-1892
In JP-A-84, a polyfluoroalkyl-based compound is used as a treating agent, and in JP-A-59-204921, a compound containing a perfluoroalkyl group is used as a treating agent.

[0008] The above-mentioned method using a treating agent is generally employed in combination with a square hollow section fiber technology. However, since it is a method in which the treating agent is adsorbed on the surface of the fiber, the treating agent easily falls off during washing of the carpet. There is a drawback that the stain resistance effect is not maintained for a long time, and further improvement has been demanded.

On the other hand, as a technique for kneading an effective drug into the fiber itself for maintaining the stain resistance for a long period of time, for example, a fluorine polymer such as a copolymer of polyethylene and tetrafluoroethylene is used. A method of kneading polyethylene terephthalate and melt-spinning to obtain a polyester fiber having excellent antifouling property, and a method of kneading a composition obtained by kneading a polyethylene polymer with polyethylene terephthalate as a sheath component and using polyethylene terephthalate as a core component. A core-sheath type composite fiber (Japanese Patent Application Laid-Open No. 62-238822) has been proposed, and a polyester fiber obtained by these improved techniques has excellent smoothness and chemical resistance, that is, stain resistance. It is said to be most suitable for use in dust-free and aseptic clothing used in manufacturing sites such as precision industries, semiconductors, and pharmaceutical foods.

However, even when the above-mentioned technology for improving the stain resistance of polyester fibers is applied to polyamide fibers for carpet as it is, sufficient crimping properties and mechanical properties as crimped fibers for carpet cannot be obtained. A crimped fiber for a carpet having both antifouling properties, texture as a carpet, elastic recovery characteristics, and durability could not be obtained.

[0011]

Therefore, the present invention solves the above-mentioned problems in the prior art, and has excellent stain resistance, maintains such excellent stain resistance for a long period of time, and has sufficient winding resistance as a carpet. An object of the present invention is to provide a crimped fiber and a carpet that have a crimping property and are excellent in durability and stain resistance.

[0012]

In order to achieve the above object, a crimped fiber excellent in stain resistance according to the present invention has a core made of polyamide and a sheath made of a polyamide containing fluorine-containing polymer. Yarn comprising a core-sheath type composite fiber comprising a polyamide composition blended at a content of 0.05 to 5.0% by weight and having a core portion of 40 to 90% by weight and a sheath portion of 10 to 60% by weight. And a crimp elongation of 10 to 40
%, Having a crimping characteristic of a crimp number of 6 to 12 pieces / inch.

[0013] The crimped fiber excellent in stain resistance according to the present invention is a random copolymer in which the fluorine-containing polymer is mainly composed of tetrafluoroethylene and ethylene, polychlorotrifluoroethylene, polyvinylidene fluoride. , Vinylidene fluoride / tetrafluoroethylene copolymer, polytetrafluoroethylene, tetrafluoroethylene / perfluoroalkylvinyl ether copolymer, and copolymers mainly composed of ethylene tetrafluoride, propylene hexafluoride and vinylidene fluoride One or more selected from polymers, the contact angle of the crimped fiber surface with water is 75 ° or more, and the contact angle with decalin is 2
0 ° or more, the single fiber fineness of the crimped fiber is 6 to 50 denier, the total fineness is 200 to 5000 denier, the cross section of the single yarn of the crimped fiber is a non-circular cross section, and the crimp It is a desirable condition that the cross section of the single fiber fiber has a hollow portion of 5 to 40%. By satisfying these conditions, a more excellent effect can be obtained.

Further, the carpet of the present invention exhibits excellent stain resistance because the above-mentioned crimped fiber is planted on a base cloth.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure and effects of the present invention will be described below in detail.

The crimped fiber excellent in stain resistance of the present invention is
The core polymer is a polyamide, and the sheath polymer is a polyamide blended with a fluorine-containing polymer such that the fluorine content is 0.05 to 5.0% by weight, and the ratio of the core is 40 to 90% by weight. A core-sheath type composite fiber having a sheath portion ratio of 10 to 60% by weight is used for at least a part of the single yarn component, and has a crimp elongation of 10 to 40% and a crimp number of 6 to 12.
It has a crimp characteristic of ケ / inch.

At least a part of the single yarn forming the crimped fiber of the present invention is the above-mentioned conjugate fiber, and a polyamide is used as a core component of the conjugate fiber. 3-3.8, especially about 2.5-3.5 is preferred.

Polyamide is nylon 6 or nylon 6.
6, even 30% by weight or less,
Usually, it may be a copolymer polyamide containing 10% by weight or less of a copolymer component. In particular, in the case of nylon 66, when forming a single yarn having a single yarn fineness of 20 denier or more, the use of a copolymerized polyamide containing about 1 to 5% by weight of a copolymer component suppresses spherulite formation during yarn production. As a result, the crimping characteristics and the mechanical characteristics are improved, and an effect such as a decrease in yarn breakage in the yarn making process can be advantageously obtained.

As the copolymerization component for the polyamide,
Diamines such as ε-caprolactam, tetramethylenediamine and hexamethylenediamine, dibasic acids such as adipic acid, sebacic acid, terephthalic acid and isophthalic acid, and salts formed from the diamines and dibasic acids are used.

Further, the polyamide includes a matting agent, a pigment,
Additives such as light stabilizers and heat stabilizers can be included as needed.

It is important that the ratio of the core of the single yarn (composite fiber) forming the crimped fiber of the present invention is 40 to 90% by weight. If the ratio of the core is less than 40%, it is difficult to obtain satisfactory crimp characteristics as a crimped fiber for carpet, while if it exceeds 90%, not only the stain resistance effect is not sufficiently obtained, but also the core-sheath. It is not preferable because the production of the mold composite fiber becomes difficult. Therefore, the ratio of the sheath portion of the single yarn (composite fiber) forming the crimped fiber is 10 to 60% by weight.

As the polyamide for the core portion and the polyamide for the sheath portion, generally, the same polymer may be used, but different types of polyamides may be used in combination.

In the core-sheath type composite fiber of the present invention, the fluorine-containing polymer to be blended with the polyamide of the sheath portion may be a fluorine-based polymer having a fluorine atom in the main chain of the polymer molecule, or a side chain of the polymer molecule. May be a fluorine-based polymer having a fluorine atom. As the latter, for example, polyperfluoroalkyl alkylates, polyperfluoroalkyl methacrylates, perfluoroalkyl acrylates and / or acrylates or methacrylates including those containing a perfluoroalkyl methacrylate and a hydroxyalkyl group And a polyester or polyether polyester containing o- or m-perfluorooxyisophthalic acid in at least a part of the dicarboxylic acid component.

Specifically, for example, a random copolymer containing tetrafluoroethylene and ethylene as main components (hereinafter, referred to as ETFE), polychlorotrifluoroethylene (hereinafter, referred to as PCTFE), polyvinylidene fluoride (hereinafter, referred to as PCTFE) , PVdF), vinylidene fluoride / tetrafluoroethylene copolymer (hereinafter, referred to as PVdF)
2F / 4F), polytetrafluoroethylene (hereinafter referred to as PTFE), tetrafluoroethylene / perfluoroalkylvinyl ether copolymer (hereinafter referred to as PF)
A) and copolymers mainly comprising ethylene tetrafluoride and propylene hexafluoride and vinylidene fluoride (hereinafter referred to as fluorine-based terpolymers).

As the ETFE, components other than tetrafluoroethylene and ethylene include monochlorotrifluoroethylene, perfluoroacrylate, perfluoroalkyl arylate, perfluoroalkyl vinyl ether, hexafluoropropylene, and vinylidene fluoride. One or more selected components may be copolymerized by about 0.1 to 10% by weight.

One or more of these polymers may be arbitrarily selected and blended with the polyamide. Among fluorine-containing polymers that are easily melt-spinned easily by blending with polyamide and have a high stain-resistance effect, ET is especially preferred.
FE and terpolymers are preferred.

The content of the fluorine element in ETFE is as follows:
The upper limit is about 69% by weight in the case of a 1: 1 copolymer of ethylene and tetrafluoroethylene, but in order to obtain the high stain resistance which is the object of the present invention, at least 40% by weight or more of fluorine atoms is required. It is preferred to contain. More preferably, an ETF containing at least 46% by weight of fluorine atoms
When E is used, it is possible to obtain a crimped fiber which is the object of the present invention and has more excellent stain resistance.

Further, as long as three components of ethylene tetrafluoride, propylene hexafluoride and vinylidene fluoride are copolymerized, the copolymerization ratio of these three components is not limited. Good, but especially ethylene tetrafluoride:
A fluorinated terpolymer composed of 5-80 mol%, propylene hexafluoride: 2-35 mol% and vinylidene fluoride: 5-90 mol% is preferred, and ethylene tetrafluoride: 30-70.
More preferably, use is made of a fluorinated terpolymer composed of mol%, propylene hexafluoride: 10 to 30 mol% and vinylidene fluoride: 10 to 50 mol%.

The content of the fluorine-containing polymer in the sheath of the composite fiber with respect to the polyamide is 0.05 to 5.0.
It is important that the content be in the range of 0% by weight, particularly 0.1 to 0.3% by weight. If the fluorine content is less than 0.05% by weight, the desired contamination resistance effect cannot be obtained. On the other hand, if the amount is more than 5.0% by weight, the spinning property is deteriorated, and the fluff and the breakage of the yarn frequently occur.

It is important that the crimped fiber of the present invention has a crimping property of a crimp elongation of 10 to 40% and a number of crimps of 6 to 12 pieces / inch. That is, the above-mentioned crimping property is a property required mainly as a crimped fiber suitable for a carpet application. When the crimping elongation is less than 10%, the bulkiness is not sufficient, and on the other hand, it exceeds 40%. Is unfavorable because it is often felt unfavorable because of a felt-like texture.

On the other hand, if the number of crimps is less than 6 pcs / inch, the bulkiness generally tends to be insufficient.

In the crimped fiber of the present invention, the intended antifouling effect is remarkably exhibited by the effect of the fluorine-containing polymer blended with the polyamide of the sheath portion of the core-sheath type composite fiber. This practical evaluation of stain resistance is performed by repeatedly stepping with shoes after carpeting, but otherwise, the contact angle between the fiber surface and water or decalin is measured and the value is measured. Scale.

The stain-resistant crimped fiber of the present invention can have a contact angle satisfying the following expression. Contact angle with water ≧ 75 ° Contact angle with decalin ≧ 20 °

If the contact angle with water is less than 75 °, water is easily adsorbed and is easily contaminated by water-soluble contaminants. The contact angle with water is preferably 80 ° or more.

On the other hand, if the contact angle with decalin is less than 20 °, oily substances are easily absorbed, and in general, they are easily contaminated by non-hydrophilic substances. The contact angle with decalin is preferably 30 ° or more.

The single fiber fineness of the crimped fiber of the present invention is preferably 6 to 50 denier, particularly preferably 10 to 50 denier. When the single yarn fineness is less than 6 denier, the texture becomes soft, but the restoring force when compressed is poor.
Exceeding denier results in a hard texture, which is not preferred.

The total fineness of the crimped fiber of the present invention is 200 to 50.
00 denier, especially 500-3500 denier, is preferred for carpets. If the total fineness is less than 200 denier, tufting efficiency is not good, which is not preferable. On the other hand, if it exceeds 5,000 denier, it is not preferable because it becomes difficult to design delicately when a pattern or pattern is provided.

In the crimped fiber of the present invention, the single yarn preferably has a non-circular cross section. The cross-sectional shape of the single yarn is bulky,
Since it is closely related to characteristics such as texture, aesthetics, compression elastic recovery, and durability, an appropriate shape may be selected according to the use of the carpet to be used.

Further, a hollow portion may be present in the cross section of the single yarn. That is, for applications in which the above-described stain resistance (dirt is less noticeable) and / or lightness and bulkiness are emphasized, crimped fibers having a hollow cross section are preferably used.
The hollow ratio of the cross section is preferably 5 to 40%.

In particular, the cross-sectional shape of the single yarn suitable for the crimped fiber of the present invention is based on a hollow, a triangular hollow, and a trilobe.

The above-mentioned crimped fiber excellent in stain resistance according to the present invention can exhibit its performance most effectively when it is planted on a base cloth and used for a carpet.
Particularly when processed into a tufted carpet, a remarkable effect is exhibited. Among them, when used for a non-cut pile carpet, the effect is most remarkably exhibited because the entire surface of the crimped fiber of the present invention is covered with the stain resistant polymer.

The crimped fiber excellent in stain resistance and the carpet comprising the same according to the present invention having the above characteristics can be produced by the following method.

That is, when producing the crimped fiber according to the present invention, first, a polyamide is prepared as a polymer used for the core portion, and a polyamide and a fluorine-containing polymer are prepared for the polymer used for the sheath portion. The polyamide for the sheath and the fluorine-containing polymer may be a previously kneaded polymer composition or may be metered and blended immediately before spinning.

Next, the core polymer and the sheath polymer are
After being melted by separate melt spinning machines, each is introduced into a composite spinning pack, each polymer is filtered, and then spun as a core-sheath composite fiber through a composite spinneret.

The composite fiber yarn spun from the composite die is
Immediately after being cooled and solidified by cold air, an oil agent containing a surfactant or the like is applied, and then wound around a roller rotating at a predetermined speed and taken off. Next, the drawn undrawn yarn is continuously drawn without being wound once. Stretching is performed in one or two or more stages. In particular, when high crimping properties are required, multi-stage stretching is preferred. Usually, a hot stretching method is adopted, and stretching is performed by applying a temperature of 150 ° C. or higher to a polymer melting point or lower.

The heat-drawn yarn is immediately introduced into a crimp processing device and crimped. In the crimping process,
Usually, crimp is given by injecting high-temperature steam from a nozzle to a yarn. Specifically, a method of applying crimp while spraying steam and yarn from a steam nozzle by injecting steam into the yarn, and crimping by allowing the steam to stay for a short time in a buckling box while injecting steam. Although there is a shaping method and the like, any method may be used.
As steam, live steam or superheated steam is used, but in any case, the steam is treated at a high temperature near the melting temperature of the polyamide.

The crimped yarn is cooled while maintaining the crimped form, then stretched, wound up after the crimp is latentified to an appropriate degree.

When a carpet having a heather pattern used for a tile carpet or the like is to be obtained, two or more kinds of metachromatic polymers are each subjected to thread-forming and crimping in the same manner as described above, followed by blending. Can be obtained by:

The crimped fiber according to the present invention can be obtained by the above method. The production of the carpet using the crimped fiber of the present invention involves passing through the steps of ordinary tufting, dyeing, and backing. Can be done by

Although the crimped fiber of the present invention has the above-mentioned properties, it is most suitable as a fiber for carpets. At the same time, it takes advantage of its excellent characteristics such as stain resistance, water repellency, oil repellency, etc. It can also be used for luggage and seats.

[0051]

EXAMPLES The present invention will be described in more detail with reference to the following examples. The characteristics of the crimped fibers used in the text and the examples, definitions of stain resistance, measurement methods, and the like are as follows. It is on the street.

[Sulfuric acid relative viscosity] 1 g of a sample was treated with sulfuric acid (concentration 9
8%) and dissolved in 100 g, and the viscosity measured by an Ostwald viscometer is referred to as "A". Further, when the measured viscosity value of only sulfuric acid (concentration 98%) in which the sample was not dissolved was defined as "B", A / B was defined as the relative viscosity of sulfuric acid.

[Strong elongation] Measured according to JIS-L-1090. [Crimp elongation] Measured according to JIS-L-1090. [Crimping number] Measured according to the staple test method of JIS-L-1015.

[Hollow ratio] The ratio (%) of the area of the hollow portion to the total area of the cross section of the fiber, which was obtained from a micrograph of the cross section of the fiber.

[Contact Angle] As a measure of water repellency and oil repellency, the contact angle on the fiber surface was measured under the following conditions. The larger the contact angle, the higher the water and oil repellency. Measuring device: Goniometer type contact angle measuring device manufactured by Elma Engineering Co., Ltd., Water contact angle measuring solution: Distilled water, Oil adhesion angle measuring solution: Decalin, Liquid proper volume: 5 μl, Measurement temperature: 20 ° C.

[Spinning properties] The spinning and stretching properties during spinning were observed and evaluated according to the following criteria. …: Good, △: slightly poor, ×: poor

[Carpet bulkiness] The carpet bulkiness was observed and evaluated according to the following criteria. Good: Good, Good: Somewhat bad, Bad: Bad [Contamination resistance] Weaving on a carpet, laying a walkway with frequent walking, and visually determining the degree of contamination at the time of a total of 40,000 people walking, the following criteria Was evaluated. …: Good, △: slightly poor, ×: poor

Examples 1 to 5 Nylon 6 polymer having a relative viscosity of sulfuric acid of 2.84 was prepared as a core polymer. On the other hand, as the sheath polymer, the same nylon 6 polymer as described above was added to ETFE (1: ethylene and tetrafluoroethylene).
(Copolymer No. 1) was prepared so that the fluorine content of the sheath became the content shown in Table 1.

Using a core-sheath type composite spinning machine, the polymer for the core and the polymer for the sheath are melted in separate melting portions, respectively, and then introduced into a composite spinning pack, and the respective polymers are filtered. Then, the core is passed through a spinneret having a discharge hole for a hollow fiber of 80 holes so that the ratio of the core portion and the sheath portion becomes the ratio shown in Table 1 and the hollow ratio becomes 12%. It was spun as a sheath-type composite hollow fiber.

The yarn spun from the die was immediately cooled and solidified with cold air, an oil agent containing a surfactant was applied, and then wound around a roller rotating at a speed of 780 m / min and pulled off. The drawn undrawn yarn is continuously drawn without being wound once and continuously drawn under a condition of a draw ratio of 3.3 times and a heating roller temperature of 180 ° C., and is immediately introduced into a crimp processing device.
The crimp was given by injecting the steam superheated to 230 ° C. from the nozzle onto the yarn.

The crimped yarn is cooled on a rotating drum while maintaining the crimped form, and then stretched to make the crimp latent to an appropriate degree.
1300 denier, crimp elongation: 30%, number of crimps: 10
C / inch polyamide crimped fiber (acid dyeable) was produced.

Further, in order to obtain a carpet having a heather pattern used for a tile carpet or the like, a cationic dyeable nylon 6 polymer having a sulfuric acid relative viscosity of 2.78 was used as the core polymer, and the same nylon 6 polymer was used as the sheath polymer. To E
Same as above except that a composition was used in which TFE (a 1: 1 copolymer of ethylene and tetrafluoroethylene) was mixed such that the fluorine content of the sheath became the content shown in Table 1. And total fineness: 1300 denier, crimp elongation:
A cationically dyeable crimped fiber with 30% crimping number: 10 pieces / inch was produced.

These acidic dyeable crimped fibers and cationic dyeable crimped fibers are combined, passed through a fiber-mixing machine, and subjected to entanglement of 40 entangles / m by air injection to give 2600
A denier, 160-filament hetero-dyed mixed yarn was prepared.

This hetero-dyed pattern mixed fiber yarn was stitched on a 1/10 gauge tufting machine at 12 stitches / m
The pile height was knitted and woven on a loop pile carpet having a height of 3.5 mm, and the carpet was led to a dyeing step, in which the acid-dyeable crimped fiber was dyed blue and the cationic dyeable crimped fiber was dyed yellow.

The carpet obtained by this method had initial carpet characteristics such as color pattern and bulkiness which were equivalent to those of a conventional carpet in which no fluorine-containing polymer was blended in fibers.

Table 1 shows the results of evaluating the stain resistance of each carpet obtained in this way by laying it on a passage where frequent walking is performed and visually determining the degree of adhesion of dirt during walking. And the degree of contamination was significantly lower than that of the conventional carpet.

[Comparative Examples 1 and 2] As in the above embodiment,
The above-mentioned ETFE was blended with the sheath nylon 6 at the ratio shown in Table 1 and spun and stretched at a composite ratio shown in Table 1 using a composite spinning machine, whereby the acid-dyeable crimped fiber and the cation-dyeable roll were drawn. Compressed fibers were made, and these were combined to give a hetero-dyed pattern mixed fiber processing yarn, thereby producing a carpet.

Table 1 also shows the evaluation results of the obtained carpets.

As a result, in Comparative Example 1, the ratio of the sheath portion was too small at 5% by weight, so that the effect of improving the stain resistance of the carpet was insufficient. Further, in Comparative Example 2, although the fluorine content of the sheath portion was too high, the stain resistance of the carpet was good, but the crimp elongation rate of the yarn was low and the bulkiness of the carpet was insufficient.

Comparative Example 3 An acid-dyeable crimped fiber and a cation-dyeable crimped fiber were prepared in the same manner as a conventional crimped fiber for carpet consisting of nylon 6 polymer alone without blending the fluorine-containing polymer. Carpets were produced by making fibers and combining them to obtain mixed-dyed patterned mixed fiber yarns.
The stain resistance of the obtained carpet was extremely poor as shown in Table 1.

[0071]

[Table 1]

[0072]

The crimped fiber of the present invention is excellent in stain resistance and has such properties that its effect is maintained for a long period of time. It has features such as easy removal of dirt by washing. Therefore, the carpet using the crimped fiber of the present invention is particularly dirty, such as a tile carpet near a doorway of an office where people frequently walk, an entrance mat, a roll carpet of a game facility, an option mat of a car, and the like. The effect is remarkably exhibited when used for applications.

The crimped fibers of the present invention are not only used for carpets but also for polyamide crimped fibers such as strings, curtains, luggage, sheets, etc., and are particularly suitable for stain resistance, water repellency and oil repellency. It can be used for required applications.

Claims (7)

[Claims] The core is made of polyamide, and the sheath is
Fluorine-containing polymer added to polyamide with fluorine content of 0.05 to 5.0
A filament containing a core-sheath type composite fiber having a core ratio of 40 to 90% by weight and a sheath portion of 10 to 60% by weight, and
A crimped fiber excellent in stain resistance, having a crimp elongation of 10 to 40% and a number of crimps of 6 to 12 pieces / inch. 2. A random copolymer comprising tetrafluoroethylene and ethylene as main components, polychlorotrifluoroethylene, polyvinylidene fluoride, vinylidene fluoride / tetrafluoroethylene copolymer, and a fluorine-containing polymer. Tetrafluoroethylene,
One or more selected from a tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer and a copolymer mainly composed of ethylene tetrafluoride, propylene hexafluoride and vinylidene fluoride The crimped fiber according to claim 1, which is excellent in stain resistance. 3. The excellent contamination resistance according to claim 1, wherein the contact angle with water on the surface of the crimped fiber is 75 ° or more, and the contact angle with decalin is 20 ° or more. Crimped fiber. 4. The stain-resistant fiber according to claim 1, wherein the crimped fiber has a single yarn fineness of 6 to 50 denier and a total fineness of 200 to 5000 denier. Excellent crimped fiber. 5. The crimped fiber excellent in stain resistance according to claim 1, wherein the crimped fiber has a non-circular cross section in a single yarn. 6. The crimped fiber having excellent stain resistance according to claim 1, wherein the single fiber cross section of the crimped fiber has a hollow portion of 5 to 40%. . 7. A carpet obtained by planting the crimped fiber according to any one of claims 1 to 6 on a base cloth.